This invention relates to winding waveguides into packs.
A waveguide is a three-dimensional structure made of a dielectric or metallic material that is capable of supporting propagating electromagnetic waves. The physical dimensions of the waveguide are such that one dimension is longer than the wavelength of the propagating wave while the other two dimensions are comparable to or shorter than the wavelength. One consequence of this physical structure is to confine the direction of the propagating wave (and therefore the signal information that the wave carries) to the direction of the waveguide's longer dimension. The waveguide also exhibits discrete propagating modes. The number of propagating modes can be altered by altering a dimension of the waveguide such as the core in the case of optical fibers.
Glass fibers are one type of optical waveguide. All glass optical fibers typically contain a silica core surrounded by a cladding layer and coated with an acrylate buffer resin to protect the core from scratches. These fibers, which are often reinforced with strengthening fibers to form a fiber cable, are used primarily for telecommunications. Both single and multiple mode fibers have been used for this purpose. Single mode fibers can support only one propagation mode at a time, while the larger core multiple mode fibers can support many such modes simultaneously.
There have been efforts to use optical fibers for communications between a vessel, e.g., a submarine, and a high velocity projectile such as a missile or torpedo. Fiber cable has been wound and stored in the projectile. Upon launch, the cable unwinds to .permit communication between the projectile and the vessel. It has also been proposed to use optical fibers to communicate between a vessel and a lower velocity projectile such as a communications buoy.